Cogeneration represents a relatively new concept in the field of generating electricity. Traditionally, electricity has been created at centralized facilities—typically through burning a fossil fuel like coal—which is then transported through an electricity grid to individual residential and commercial facilities.
Within the past several years, cogeneration systems have been developed to essentially reduce both need and reliance on these grids. More specifically, cogeneration systems employ a heat engine (typically a combustion engine) or power station located at the residential or commercial facility itself to simultaneously generate both electricity and useful heat. Most cogeneration systems use a centralized reservoir of fossil fuel to create electricity, heat running water and air and often provide energy back into the grid for credit.
Recently, there have been several forms of cogeneration systems developed for use in residential homes and smaller commercial facilities. These systems have been dubbed “mini-cogeneration” systems—due to their modest size and performance. Another common name associated with these systems is a distributed energy resource (“DER”) system.
Regardless of moniker, these systems produce usually less than 5 kWe. Instead of burning fuel to merely heat space or water, some of the energy is converted to electricity in addition to heat. This electricity can be used within the home or business or, if permitted by the grid management, sold back into the electric power grid. A recent study by the Claverton Energy Research Group found that such a co-generation system offered the most cost effective means of reducing CO2 emissions—even compared to use of photovoltaics.
Apart from the energy conversation associated with mini-cogeneration systems, the technology also offers additional logistical benefits. Such cogeneration systems often offer more reliable energy solutions to residential dwellings in rural areas in which it is difficult to gain access to the grid. Alternatively, these systems offer more stable energy supplies in areas often affected by natural disasters such as hurricanes, tornadoes and earthquakes—where the downing of power lines will often lead to large periods with a lack of energy.
While there exist multiple benefits for micro-cogeneration systems, they currently possess several drawbacks. First, current cogeneration systems still create a certain degree of byproduct from the burning of fossil fuels that must be released into the atmosphere. This creates a secondary safety issue as there is a risk that unless this toxic byproduct is sufficiently vented that it could cause a build up of carbon monoxide within the residence. Second, most of the heat engines used in micro-cogeneration systems are not highly efficient resulting in waste of expensive fossil fuels. Finally, many co-generation systems fail to adequately harvest all of the heat by-product created from the heat engines—which could be used to heat air and water used throughout the residence.
Accordingly, there is a need in the field of micro-cogeneration systems for a highly efficient system that creates more electricity resulting in less venting of by-product. Moreover, such system should ensure greater capture of usable heat for purpose of warming air and/or water for use in the home. Finally, such improved system should preferably be compact, self-contained and easy to use.